Fetal development of primate chemosensory corpuscles. I. Synaptic relationships in late gestation

1983 ◽  
Vol 213 (2) ◽  
pp. 146-162 ◽  
Author(s):  
Daniel S. Zahm ◽  
Bryce L. Munger
Keyword(s):  
Fetal Development ◽  
Late Gestation

Effects of Maternal Nutrient Restriction During Gestation on LH Production in the Female Bovine Fetus

2021 ◽  
Vol 99 (Supplement_2) ◽  
pp. 25-26
Author(s):  
Sterling H Fahey ◽  
Sarah West ◽  
John M Long ◽  
Carey Satterfield ◽  
Rodolfo C Cardoso
Keyword(s):  
Protein Content ◽  
Fetal Development ◽  
Monozygotic Twins ◽  
Late Gestation ◽  
Nutrient Restriction ◽  
Western Blots ◽  
Physiological Processes ◽  
Individual Potential ◽  
The Individual

Abstract Gestational nutrient restriction causes epigenetic and phenotypic changes that affect multiple physiological processes in the offspring. Gonadotropes, the cells in the anterior pituitary that secrete luteinizing hormone (LH) and follicle-stimulating hormone (FSH), are particularly sensitive to nutritional changes during fetal development. Our objective herein was to investigate the effects of gestational nutrient restriction on LH protein content and number of gonadotropes in the fetal bovine pituitary. We hypothesized that moderate nutrient restriction during mid to late gestation decreases pituitary LH production, which is associated with a reduced number of gonadotropes. Embryos were produced in vitro with X-bearing semen from a single sire then split to generate monozygotic twins. Each identical twin was transferred to a virgin dam yielding four sets of female twins. At gestational d 158, the dams were randomly assigned into two groups, one fed 100% NRC requirements (control) and the other fed 70% of NRC requirements (restricted) during the last trimester of gestation, ensuring each pair of twins had one twin in each group. At gestational d 265, the fetuses (n = 4/group) were euthanized by barbiturate overdose, and the pituitaries were collected. Western blots were performed using an ovine LH-specific antibody (Dr. A.F. Parlow, NIDDK). The total LH protein content in the pituitary tended to be decreased in the restricted fetuses compared to controls (P < 0.10). However, immunohistochemistry analysis of the pituitary did not reveal any significant changes in the total number of LH-positive cells (control = 460±23 cells/0.5 mm2; restricted = 496±45 cells/0.5 mm2, P = 0.58). In conclusion, while maternal nutrient restriction during gestation resulted in a trend of reduced LH content in the fetal pituitary, immunohistological findings suggest that these changes are likely related to the individual potential of each gonadotrope to produce LH, rather than alterations in cell differentiation during fetal development.

Alterations in oxytocin prohormone processing during early development in the fetal sheep

1992 ◽  
Vol 263 (3) ◽  
pp. R738-R740 ◽  
Author(s):  
M. Morris ◽  
M. Castro ◽  
J. C. Rose
Keyword(s):  
Fetal Development ◽  
Plasma Levels ◽  
Umbilical Artery ◽  
Umbilical Vein ◽  
Late Gestation ◽  
Developmental Changes ◽  
Fetal Sheep ◽  
Fetal Plasma ◽  
Prohormone Processing ◽  
Specific Antisera

Oxytocin (OT) prohormone processing was studied in fetal sheep. Using specific antisera that recognize the amidated and the COOH-terminal extended forms of OT, we measured arterial and venous levels of the OT peptides in fetal sheep plasma at 94 and 138 days of gestation. Plasma levels of the COOH-terminal extended forms, OT-X, were highest early in development, 35.7 +/- 9.8 vs. 14.3 +/- 5.7 pg/ml (94 vs. 138 days). The ratio of the plasma peptides, OT-X to OT, was higher in the young fetus (35 +/- 11.6 vs. 3.1 +/- 1.3, 94 vs. 138 days). There were also developmental changes in the umbilical artery-umbilical vein differences, with positive values noted in late gestation. These results demonstrate that the changes in the processing of the OT precursor that occur during fetal development are reflected by alterations in the relative amounts of prohormone and amidated hormone found in fetal plasma.

Cytokines and cytokine receptors in fetal growth and development

2001 ◽  
Vol 29 (2) ◽  
pp. 33-37 ◽  
Author(s):  
M. E. Symonds ◽  
A. Mostyn ◽  
T. Stephenson
Keyword(s):  
Fetal Growth ◽  
Fetal Development ◽  
Early Stage ◽  
Critical Role ◽  
Late Gestation ◽  
Cytokine Receptors ◽  
Prolactin Receptors ◽  
Factor I ◽  
Specific Effects ◽  
Pathological Conditions

The cytokine receptors for growth hormone (GH), prolactin and leptin have a critical role in regulating embryo, placental and/or fetal development, which is dependent on stage of gestation and species. GH and prolactin receptors are detectable from conception, and alterations in the maternal hormonal environment may impact on placental growth from this early stage of gestation. Leptin is critical for conception, but its role in fetal growth remains elusive. During late gestation, when fetal growth accelerates and organ maturation occurs, prolactin and insulin-like growth factor-I may have interactive roles in regulating the growth of specific tissues, including adipose tissue. Prolactin, leptin and GH all have specific effects on fetal and neonatal energy balance, which are mediated in part through promoting lipolysis and/or enhancing the expression of uncoupling proteins. An increased understanding of these interactions is likely to have important implications for a number of potentially pathological conditions, including infection, obesity and hypertension.

scholarly journals Exogenous genistein in late gestation: effects on fetal development and sow and piglet performance

animal ◽  
2016 ◽  
Vol 10 (9) ◽  
pp. 1423-1430 ◽  
Author(s):  
C. Farmer ◽  
P. Robertson ◽  
C.W. Xiao ◽  
C. Rehfeldt ◽  
C. Kalbe
Keyword(s):  
Fetal Development ◽  
Late Gestation

Fetal canine cardiac Purkinje fibers: electrophysiology and ultrastructure

1984 ◽  
Vol 246 (2) ◽  
pp. H250-H260
Author(s):  
P. Danilo ◽  
R. F. Reder ◽  
O. Binah ◽  
M. J. Legato
Keyword(s):  
Action Potential ◽  
Fetal Development ◽  
Late Gestation ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Purkinje Fibers ◽  
Ultrastructural Studies ◽  
Surface Areas ◽  
Cardiac Purkinje Fibers ◽  
External Potassium

We studied the ontogenesis of the transmembrane action potential and the ultrastructure of fetal canine Purkinje fibers. Fetal hearts were obtained from fetuses just after implantation to end gestation. Using standard microelectrode recording techniques, we found that action potential characteristics varied linearly over this period of development. Maximum diastolic potential (MDP) ranged from -65 to -85 mV; action potential amplitude (AMP) varied from 100 to 120 mV; maximum upstroke velocity (Vmax) increased from 200 to 550 V/s. Action potential duration measured to 50% repolarization (APD50) increased from 15 to 156 ms while duration measured at full repolarization (APD100) similarly increased from 75 to 236 ms. The relationship between external potassium concentration and membrane potential was equivalent across all stages of fetal development. Tetrodotoxin (TTX, 7.7 X 10(-7) to 1.6 X 10(-5) M) caused concentration-dependent decreases in AMP, Vmax, and APD50. Verapamil (1 X 10(-7) to 1 X 10(-5) M) decreased Vmax and APD50 in a concentration-dependent manner. The effects of both TTX and verapamil were statistically equivalent across all stages of fetal development. Ultrastructural studies of fetal Purkinje fibers showed that myocytes at the earliest stages of development (Purkinje fibers were not visually distinct at this time) were arranged as a tightly packed mosaic with a rounded shape, with a large amount of glycogen, small sparse mitochondria, and relatively large nuclei. Mitotic cells were observed frequently. Purkinje fibers when first identified grossly had fewer myofilaments than working myocardial cells and sarcomeres without M lines. By late gestation, intercalated disks appeared with an increase in surface areas; desmosomes occurred more frequently. Myofilaments are organized around Z bands into rudimentary sarcomeres that still lack M lines. These data indicate that, although the fetal canine Purkinje fiber undergoes marked developmental changes in ultrastructure, cellular electrophysiological changes are more subtle. The action potential has a qualitative appearance similar to those of the neonatal or adult fiber. At no time during fetal development could we find slow-response action potentials.

Heat Stress Effects on Fetal Development during Late Gestation in the Ewe

1977 ◽  
Vol 44 (3) ◽  
pp. 442-446 ◽  
Author(s):  
D. E. Brown ◽  
P. C. Harrison ◽  
F. C. Hinds ◽  
J. A. Lewis ◽  
M. H. Wallace
Keyword(s):  
Heat Stress ◽  
Fetal Development ◽  
Late Gestation ◽  
Stress Effects

scholarly journals Altering ewe nutrition in late gestation: II. The impact on fetal development and offspring performance1

2015 ◽  
Vol 93 (10) ◽  
pp. 4873-4882 ◽  
Author(s):  
F. M. McGovern ◽  
F. P. Campion ◽  
T. Sweeney ◽  
S. Fair ◽  
S. Lott ◽  
...  
Keyword(s):  
Fetal Development ◽  
Late Gestation ◽  
The Impact

scholarly journals PSII-34 Placental GLUT3 (SLC2A3) RNA interference: Impact on fetal growth at mid-gestation

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 378-378
Author(s):  
Cameron Lynch ◽  
Asghar Ali ◽  
Victoria Kennedy ◽  
Amelia R Tanner ◽  
Quinton A Winger ◽  
...  
Keyword(s):  
Rna Interference ◽  
Fetal Development ◽  
Glucose Transporter ◽  
Basolateral Membrane ◽  
Venous Blood ◽  
Late Gestation ◽  
Tissue Samples ◽  
Femur Length ◽  
The Impact ◽  
Tibia Length

Abstract Glucose is the predominant energy substrate for fetal oxidative processes and growth, and is taken up by the placenta and transported to the fetus by the facilitative transporters GLUT1 (SLC2A1) and GLUT3 (SLC2A3). SLC2A1 is the most abundant placental transporter, and as such is believed to be the primary glucose transporter in human and sheep placenta. However, SLC2A3 exhibits a six-fold greater glucose transport capacity, and in sheep, SLC2A3 is localized to the apical trophoblast membrane, whereas SLC2A1 is predominantly localized to the basolateral membrane, indicating that both may be required for optimal fetal development. It was our objective to use placenta-specific RNA interference (RNAi) to diminish SLC2A3, and determine the impact at mid-gestation (75 dGA) in sheep. Single hatched blastocysts were harvested and the trophectoderm was infected with lentiviral constructs expressing either a scramble control (SC) or SLC2A3-specific (GLUT3-RNAi) short-hairpin RNA, and then surgically transferred into a synchronized recipient. The resulting pregnancies underwent ultrasound Doppler velocimetry and fetal measurements at 70 dGA, and a terminal surgery at 75 dGA for collection of uterine and umbilical arterial and venous blood, fetal and placental measurements and tissue samples. Due to a lack of fetal sex x treatment interactions, statistical comparisons between SC (n = 6) and GLUT3-RNAi (n = 6) pregnancies were made by Student’s T-test. At 70 dGA, while umbilical artery velocimetry was not impacted, biparietal diameter (P ≤ 0.10), femur length and tibia length (P ≤ 0.05) were reduced in GLUT3-RNAi pregnancies. These results were confirmed at 75 dGA surgery, as GLUT3-RNAi fetuses had reduced fetal weight (P ≤ 0.10), head circumference (P ≤ 0.05), femur length (P ≤ 0.05), and tibia length (P ≤ 0.05). While it has been suggested that GLUT3 is predominantly important in late gestation, these preliminary data indicate that GLUT3 is important for normal fetal development during the first-half of gestation as well. Supported by NIH grant HD094952.

scholarly journals Adiponectin Expression in Human Fetal Tissues during Mid- and Late Gestation

2005 ◽  
Vol 90 (4) ◽  
pp. 2397-2402 ◽  
Author(s):  
S. Corbetta ◽  
G. Bulfamante ◽  
D. Cortelazzi ◽  
V. Barresi ◽  
I. Cetin ◽  
...  
Keyword(s):  
Cord Blood ◽  
Fetal Development ◽  
Venous Blood ◽  
Late Gestation ◽  
Maternal Circulation ◽  
Arterial Walls ◽  
Fetal Tissues ◽  
White Adipocytes ◽  
General Decline ◽  
Human Fetal Tissues

Abstract Adiponectin (ApN), an adipocytokine expressed in adipocytes with antidiabetic and antiatherogenic actions, has been detected in cord blood, suggesting a putative role in intrauterine fetal development. The aim of this study was to confirm the presence of ApN in the fetal circulation and directly investigate ApN expression in fetal tissues. The study showed high ApN levels in umbilical venous blood from fetuses [n = 44; 31.2 ± 14.1 (sd) mg/liter in umbilical vs. 8.4 ± 4.0 in maternal circulation (P < 0.0001)] that positively correlated with gestational age. By using RT-PCR, Western blotting, and immunohistochemistry, ApN was detected in several fetal tissues at mid- and late gestation (from 14 to 36 wk) but not in the placenta. ApN was expressed in tissues of mesodermic origin, i.e. brown and white adipocytes, skeletal muscle fibers of diaphragm and iliopsoas, smooth muscle cells of small intestine and arterial walls, perineurium and renal capsule, and tissues of ectodermal origin, i.e. epidermis and ocular lens. The distribution of ApN expression in nonadipose tissues showed a general decline during the progression of gestation. The unexpected pattern of ApN expression in the human fetus may account for the high ApN levels in cord blood and predicts novel roles for ApN during fetal development.

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